Implement a Java program to find the GCD (Greatest Common Divisor) of two numbers.

Here’s a Java program to find the GCD (Greatest Common Divisor) of two numbers:

import java.util.Scanner;

public class GCD {
    public static void main(String[] args) {
        int num1, num2, gcd;
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the first number: ");
        num1 = scanner.nextInt();
        System.out.print("Enter the second number: ");
        num2 = scanner.nextInt();
        gcd = findGCD(num1, num2);
        System.out.println("GCD of " + num1 + " and " + num2 + " is " + gcd);
    }

    public static int findGCD(int num1, int num2) {
        if (num2 == 0) {
            return num1;
        }
        return findGCD(num2, num1 % num2);
    }
}

In this program, we first take user input for two numbers. We then call the `findGCD()` method to find their GCD.

The `findGCD()` method takes two integer parameters `num1` and `num2` and returns their GCD as an integer. We use the Euclidean algorithm to find the GCD. If `num2` is 0, then we return `num1` as the GCD. Otherwise, we recursively call the `findGCD()` method with `num2` and the remainder of `num1` divided by `num2` as arguments. We repeat this process until `num2` becomes 0.

At the end of the program, we print out the GCD of the two numbers.